Telephone system.



H. B. STONE.

TELEPHONE SYSTEM.

APPLIUATION FILED APR.1e.19o9.

946,746. y Patented. Nov. 23, 1909.

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H. B. STONE.

TELEPHONE SYSTEM.

APPLICATION FILED 1113.16, 1909.

940,746. Patented Nev. 23, 1909.

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@1%27 Jmwm H. B. STONE.

TELEPHONE SYSTEM.

APPLICATION FILED 11.16, 1909.

940,746. Patented Nov.23,1909.

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H. vB. STONE. TELEPHONE SYSTEM.

APPLICATION FILED APEL 16, 1909.

946,746. i Patented Nov. 23, 1909.

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H. B, STONE.

TELEPHONE SYSTEM.

APPLICATION FILED APB. 1e, 1909.

940,746. Patented Nov, 23, i909,

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transformer.

HENRY B. STONE, 0F ERGVIDENCE, RHQDE ISLAND.

TELEPHONE SYSTEM.

Specification of Letters Patent.

Patented Nov. 23, 1969.

Application led April 16, 1999. Serial No. 499,278.

T 0 all whom it may concern:

Be it known that I, HENRY B. S'roxn, a citizen oi the United States, and a resident of Providence, in the county ot' Providence and State ot Rhode island, have invented a new and useful improvement in Telephone Systems, ot which the following is a speciication.

y invention relates to telephony and its o'l'iject is to provide a telephone system wherein the receiver at a station will be unai'i'ected by the operation ot a transmitter at the same station.

in carrying out my invention i employ a receiving circuit which includes an electroresponsive device, such as a telephone receiver ot an ordinary sub-station set or a receiver of a repeating set or an oscillation detector ot a wireless telephone set, and one of the windings of a transformer, the windings of which are conductively connected; a transmitting circuit associated with said receiving circuit and including` the other winding of said transformer; and a transmitter associated directly or indirectly' with said transmitting circuit and arranged to vary a suitable source of energy in accordance with the sound waves accompanying articulate speech; and I may employ snita le means for regulating the inductive ett'ect between the windings of said The main line in the case of wire telephonyv or the antenna in the case of ,vircless telephony may be associated directly or 'indirectly with said receiving circuit. The arrangement of circuits above briefly described may be employed in telephony in a number of ways some of which are hereinafter set forth and all ot which depend upon the tact that the receiver or other electro-responsive device is rendered immune from disturbance by local transmitting currents.

My invention will be explained in connection with the drawings which accompany and term a part ot this specification and which show in diagram various circuit arrangements whereby the above mentioned object ma ,v be carried into ei'iect.

in the dawings-Figures l to 'T' inclnsive show telephone repeater systems ein* bmlying my invention. Figs. 8 to l0 inclusive show local-battery anti-side-tone sys tems embodying my invention. Fig. l2 shows the application of my invention to a composite signaling system. `Figs. i3 to l5 inclusive show tlie application of my invention to an anti-side-tone wireless telephone system. Fig. 16 shows a wire-wireless telephone repeater system embodying my invention. Figs. ll and 17 show the application of my invention to a common-battery anti-side-tone system.

Figs. l and 8 have been introduced to show the simplest forms of my invention. lThe more practical forms thereof are illustrated in the other tigures.

ln Figs. l and 8, l, 2 are the windings ot a transformer which are conductively connected at the point P which may be a binding post. Tn Fig. l the receiving circuit comprises the winding l and lthe repeater-receiver and the transmitting circuit includes the other winding' 2, the battery i and the repeater-transmitter G. ln Fig. 8 the receiving circuit includes the winding l and the receiver R, and the transmitting circuit includes the winding 2, the battery a and the transmitter T. in i? ig. l, which represents a wire telephone repeater system, the transmitter is actuated by the receiver 5. in Fig. 8 which represents a local-battery anti-side-tone system, the transmitter T is operated in the usual way by the subscriber and is ot course independent ot the receiver R.

The windings l, are shown in the present instance as wound in the same direction, although it will be understood that it is necessary only that they should be arranged to produce opposite magnetic effects. number ot' means may be employed for regulating the inductive ettiect bet 'een the windings l, 2, such as means tor varying the number oil turns of one ot the coils or for varying their relative position, a variable resistance connected in shunt around one winding, a non-magnetic conducting tube inserted between the windings and the core on which they are wound, etc., all ot which are i well known in the art and require no turther onv the core shown at 8 in Figs. 13 to 1G inclusive may be made by embedding finely 'f comminuted iron in a dielectric matrix such as mixture of beeswax and rosm 1n the manner well known in the art of wireless telegraphy, or preferably the windings are arranged to be relatively movable.

rlhe circuit arrangements shown in Figs. 1 and 8 may be connected with the main line by means of the binding posts P P.

The operation of the systems shown 1n Figs. l and 8, which is substantially the same as that of the systems illustrated in the other gures, is as follows: In the case of Fig. l the incoming current impressed upon the system at the points P P energizes the repeater-receiver which in turn actuates the repeater-transmitter 6 and causes pulsations of current from the battery et to pass out over the line, these pulsations being of much larger amplitude than those of the incoming current which initiate the action oi the repeater-receiver. By suitable adjustment of the inductive eiilect between the windings l, 2, as by the adjustment of the core 3, the ettect of the variable component of the current from the battery 4L on the repeater-receiver is counteracted, the magnetic eect of such variable component in the winding 2 counteract-ing or neutralizing in whole or in part the eitect thereotl in the winding 1, and thereby the repeater system is prevented from continuous operation colnmonly known as"-singin r.

rlhe operation of the system shown in Fig. 8 is the same as that above described in connection with Fig. l with the exception that the pulsations of battery current are created by the operator speaking into the transmitter T. By the counteraction of the variable component of these battery pulsations on the receiver R, the latter remains quiet .while the operator is speaking-in other words, the side-tone l" usually created in a receiver by speaking into the transmitter associated therewith is eliminated.

1t will be obvious that the arrangement of the windings 1, 2 is such that their inductive effect will not prevent th'e incoming currents from acting upon the receiver R or upon the repeater-receiver 5 inasmuch as that portion of said currents which passes into the transmitter circuit and through the winding 2 develops in the winding 1 currents flowing through said winding 1 in the same direction as the incoming currents; and that said arrangement is such as to counteract the variations of potential impressed upon the point P by the locally-developed transmitting currents.

inasmuch as the variable component only of the current in the transmitting circuit causes singing7 in a repeater system or side-tones in an ordinary set, the steady flow of current in said circuit through the receiving circuit may be prevented in any suitable manner as by including a condenser in series with said receiving circuit or by connecting the transmitter and battery in a circuit separate from the transmitting circuit and inductively related thereto. EX- amples ot such use or' a condenser are shown in Figs. 7, l1 and l2, and the inductive association of the transmitter and battery with the transmitting circuit is shown in Figs. 2 to G inclusive and in Figs. 9 and l0.

In Fig. 2 the transmitter 6 is included in series with the battery 4 and the winding 8 of a repeating coil, the other winding 9 of which terms part of the transmitting circuit and is connected in series with the winding ln Fig. 9 the transmitter T is connected in series with the battery l and the winding 8 and the latter is inductively related with the winding 9 of the transmitting circuit.

The preferred arrangement is shown in Figs. 3 and 10 in which the transmitting and receiving circuits, which are connected to the binding posts P P are not connected directly with the main line but are inductively associated therewith through the intermediary of the transformer, the windings of which are shown at 10, 11, the former being connected to the binding posts P P and the latter to the binding posts Q Q to which the main line may be connected. The advantage ot the systems shown in Figs. 3 and l() over those hereinbefore described is that the winding lO provides a continuously closed circuit for the apparatus connected to the binding posts P P and thereby renders the same less sensitive to changes in external conditions.

One way in which the system shown in Fig. 3 may be connected with the main line is shown in Fig. t in which S S represent terminal stations and 11 a winding similar to the winding l1. The winding l0 is inductively related to the windings 11 11 which are connected serially with the two sides ot the main line respectively and serve to maintain the balance of the latter. 'Vhen the repeater system is serially connected with the main line through the transformer or repeating coil 10, 11, 11', the variations of current developed in the line by the operation of the distant transmitter will be intensified.

Another way in which the apparatus above described may be connected with the main line is shown in Fig. 5 in which the system illustrated in Fig. 2 is bridged across said main line at a point between the stations S S. lVhen the repeater system is bridged across the main line or connected in shunt therewith as shown in Fig. 5, the variations in potential between the points P P produced by the operation of the distant transmitter will be intensified.

A third method of applying my invention is shown in Fig. 6 in which E, lV represent all-metallic normally-closed main lines including the windings 11, l1', respectively,

each ot which is inductively related with one ot the coils l0, 10 connected with the repeater system. lhen a repeater system is connected in series or in shunt with a main line in the manner shown in Figs. and 5, a certain portion of the energy of the line passes from one section to the other without assisting in the operation of the repeater-recciver.

.However when the two repeater systems are connected in the manner shown in Fig. t3, the two sections lil, lll will work reciprocally and none ot' the energy ot one can pass to the other without imparting energy to one ot the repeaterreceivers. ln the system shown in (3, as in those above described. the ditlerential transformer 1, 2 protects the repeater-receiver vtrom the etl'ect ot pulsations trom the battery et and the transformer l. 2 protects the repeater-receiver` 5 from the ett'ect of pulsations trom the battery 4.,

Fig. i shows the application ot my invention to a repeater system located at the subscribei"s sub-station in a common-battery system having a central source of energy 4H and repeating coils L L. The subscribers set is shown in the present instance as comprising the condenser 12, bell 13, hooliswitch 1l, repeating coil 15. and transmitter 'lfp 1G represents a condenser, the function ot which has already been described. The system shown in Fig. 7 is designed especially tor long-distance transmission and its operation is as follows: lllhen the hook-switch is raised, incoming currents will energize the repeater-receiver 5 thereby actuating the repeater-transmitter (3 and creating pulsations in the current otf the battery 4 which in turn actuate the local receiver l. Current pulsations ot the said source 4 initiacted by speaking into the transmitter T1 energize the` repeater-receiver 5 thereby actuating the repeater-transmitter 3 and causing impulses ot the central source ot energy to be impressed upon the main line and actuate the receiver at the distant station. The iiicoming current pulsations even although too weak to operate etl'ectively the local receiver 1?.. will actuate the repeaterreceiver 5 sulficiently to cause the repeatertraiismitter b to develop pulsations in the current ot the local source which are of sutiicient amplitude to operate the local receiver R. The repeater-receiver 5 is rendered independent of such reinforced pulsations produced by the operation ot the repeatertransmitter 3 by means ot the transformer 1, 2 and its adjustable core ln Fig. 11 l have shown two ways in which my invention may be applied to a common-battery system for preventing sidetones. rThe condenser 16 prevents the steady flow of current through the receiver l in both cases. The transmitter T which is connected in series with the winding Q and to one side ot the main line creates pulsations of the common battery current, the etfect of which on the receiver l?. is neutralized by the windings 1, 2 as above explained. rl`he tansmitter 'lw which is connected in series with both windings 1. 2 and to one side of the line creates pulsations ot` common-battery current. the etect et' which on the receiver R is neutralized by said windings iiother way ot' preventing side tones iu a conmion-battery system shown in Fig. 1T wherein the receiver E is bridged across the line through the intermediary ot the transformer stat, 45 and the transmitter T1" is connected between one side of the line and a point between the terminals ot the winding let. rlhe pulsations produced by the transmitter in the current ot the central battery im flow through thc winding -lin opposite directions and their effect upon the winding 15 and the receiver lt is therefore neutigalized. The condenser 1G may be employed as shown to exclude the steady tlow ot current from the winding 441-.

in Fig. 12, which represents a portion ot a composite signaling system, 1T is a telegraph ltey, 1S the source ot telegraph current, and 19 a relay, all connected in series with the winding and with the main line. 2O is a condenser and 21 represents a complete telephone set im'fludiug a transmitter. a receiver and a source of energy. The condenser and telephone set are connected in series with the winding 1 and with the main line. ln composite signalingl sy tems as usually constructed, the telephone ringing-current tends to actuate the telegraph relay and the telegraph signaliiig-current tends to operate the telephone receiver. fr condenser usually is employed to exc nde the telegraph current from the telephone branch and an inductance coil to exclude the telephone current from the telegraph branch. In the present instance these functions are pert'ormed by the condenser 2O and the transformer 1, 2, respectively, and additional security against interlierence between the telegraph and telephone branches. especially interference with the telephone branch by the telegraph current, is aiiorded by the particular arrangement ot the windings 1, 2, by means of which the e'l'tect ontl the telegraph transmitter currents on tie telephone receiver is counteracted.

In Fig. 3, l have shown the application ot my invention to an auti-sidc-toue wireless telephone system. 21 represents an antenna connected to the binding posts l P ot' an ar angement or" circuits similar to that shown in Fig. i) with the exception that the electro-responsive device which it is desired to protect from the currents in the transmitting circuit an oscillation detector l) and with the further exception that the windings 1, Q and the core 3 are constructed to meet the requirements of high frequency working. 38 is a potentiometer and Bet a telephone receiver connected with the oscillation detector and constituting the usual local circuit. 22 is a condenser which may be employed to tune the circuit which includes the oscillation detector. S, 9 are the windings of a transformer associating the antenna with any suitable source of high frequency current, such for example .as the so called singing-arc circuit including the arc 21, condenser 25, and primary S. 27 is a source of direct current connected with the arc through the resistance or inductance 26 a-nd transmitter 28. It will be understood of course that any suitable source of high frequency current may be employed.

In F ig. 141 the antenna is connected to the binding posts Q Q of an arrangement of circuits similar to that shown in F ig. 10 with the exceptions above noted in the description of Fig. 13 and of the still further exception that the transformer 10 11 is designed to meet the requirements of high frequency working.

The high frequency current impressed upon the transformer S", 9 in Figs. 13 and 141-, will create electrical oscillations in the antenna, but will not affect the detector D or its associated telephone receiver Se because of the neutralization of the effect on said detector of the transmitting current by the transformer l, Q". late the inductive effect between the windings of said transformer I prefer to vary their relative position although the commiiiuted iron core 3 above described may be employed.

ln Fig. 15 the high frequency oscillations are impressed upon the antenna by the autotransformer 3Q, 32. rIhe primary 30 is connected in series with the winding 2, and the circuit which includes the auxiliary coil 31, inductively associated with the auto-transformer, the condenser 29 and the detector D, is connected in series with the winding 1. In this case the high frequency transmitting currents are neutralized with respect to the detector D vby means of the transformer 1, Q and the auxiliary coil 231 in aY manner that will be obvious.

In Fig. 1G I have shown the application of my invention to a system whereby a wireless telephone system may be operated by a wire telephone system and a wire telephone system by a wireless telephone system. In this particular instance I have shown the adaptation of the wire-telephone repeater system illustrated in Fig. t3 to a wire-to-wireless system, IV in both cases representing a wire-telephone trunk line and E in Fig. 16 representing a wireless telephone system into which the wire system 1V may repeat and In order to regu# which in turn may repeat into the wire system 1V. 4 represents a high frequency source such as the source shown in F ig. 13, connected in sei'ies with the transmitter G. Telephone pulsations impressed upon the system IV at a distant station pass through the winding 1 and actuate the repeater-receiver 5. therebycausing the repeater-transmitter G to vary the high frequency current in accordance with said pulsations and thereby impress upon the antenna through the transformers 8, 9 and 10, 11 high frequency current similarly modified or varied. The transformer 1, 2 protects the detector D ifn the manner hereinbefore described from the effect of said high fre` qucncy current. Electromagnetic waves iinpingiiig upon the antenna from a distant transmitting station create oscillations which actuate the detector and the repeaterreceivei 5, the latter in turn causes the repeater-transmitter 6 to create pulsations in the current of the battery 4, and these pulsations are sent out over the line IV by means of the transformers 8, 9 and 10, 11. By means of the transformer 1, 2, with its adjustable core 3 the repeater-receiver 5 is protected from the effect of the said battery pulsations sent over the system IV.

It will be understood that the particular embodiments of my invention herein specically described for the purpose of more fully explaining the principle thereof may be subjected to a wide range of variation without departing from said principle. The several means for regulating the inductive effect between tlie windings of the transformer, al-

though often convenient and in fact esseiii tial when my invention is used in lines the conditions of which are not constant, are nevertheless unnecessary when my invention is used in lines the conditionsof which are not variable. In such case the transformer coils may be designed with respect to the line to which they are to be connectedv and no such regulating means will be required.

I claim:

1. In a signaling system, the combination with a. circuit including an electro-responsive device and one of the windings of a transformer, of a transmitting circuit associated with said circuit and including the other winding of said transformer, said windings being conductively connected, a signaling device and source of energy associated with said transmitting circuit, and means for regulating the inductive effect between said windings.

2. In a telephone system, a receiving circuit including a receiver and one of the windings of a transformer, a transmitting circuit associa-ted with said receiving circuit and including the other winding of said transformer, said windings being conductively connected, a transmit-ter and source of azionare 'energy associated with said transmitting circuit, and means for regulating the inductive etiect between said windings.

3. in a telephone system, a receiving circuit including a receiver and one of the windings of a transformer, a transmitting circuit associated with said receiving circuit and including the other winding of said transformer, said windings being` conductively connected, a transmitter and source of energy associated with said transmitting circuit, and a core for said windings adjustable with respect thereto.

in a telephone system, a receiving circuit includ'ig a receiver and one of the windings of a transformer, a transmitting circuit associated with said receiving circuit and inciuding the other winding' of said transformer, said windings being conductively connected, a transmitter and source of energy associated with said transmitting circuit, means for regulating the inductive effect between said windings, and a line circuit associated with said receiving and transmitting circuits.

ln a teiephone system, a receiving circuit including a receiver and one of the windingsl of a transformer, a transmitting circuit associated with said receiving circuit and including the other winding of said trans' nier, said windings lacing conduct'- ively connected, a 'transmitter' and source of energy associated with said transmitting circuit. means for regulating the inductive effect between said windings` a closed circuit coin'luctively connected with said transmitting and receiving circuits and a .line circuit associated with said closed circuit.

t3. in a telephone system, a receiving circuit including a receiver and one of the windings of a transformer, a transmitting circuit' associated with said receiving circuit and including the other winding of said transformer, the said windings being conductively connected, a transmitter and source of energy associated with said transmitting circuit, means for regulating the inductive etfect between said windings, a closed circuit eonductively connected with said transmitting and receiving circuits and a line circuit inductiveiy related to said closed circuit.

7. ln a telephone system, a receiving circuit including a receiverI and one of the windings of a transformer, a transmitting circuit associated with said receiving circuit and including the other winding of said transformer, the said windings being conductively connected. a transmitter and source of energy a ciated with said transmitting circuit, means for regulating the inductive effect between said windings, a line circuit and means associating' said transmitting and receiving circuits serially with said line circuit point between the terminal stations.

S. in a telephone system, a receiving circuit including a receiver and one oitI the windings of a transformer, a transmitting circuit associated with said receiving circuit and including the other winding of said transformer, said windings being conductively connected, a transmitter and source of energy associated with said transmitting circuit, means for regulating the inductive effect hetween said windings, a line circuit and a transformer having three coils, one coil being conductivcly connected to said transmitting and receiving circuits and the other two being connected in series with the two sides of the line circuit, respectively.

t). ln a signaling system, the continuation with a circuit including' an electro-responsive device and one of the windings of a transformer, of a transmitting circuit associated with said circuit and including the other winding of said transformer, said windings heing conductively connected both terminals, a signaling device and a source of energy associated with said transmitting circuit.

10. ln a telephone system, a receiving circuit including a receiver and one of the windings of a transformer, a transmitting circuit ssociated with said receiving circuit and including' the other winding of said transformer, said windings heing conductively connected at both terminals, and a transmitter and source of energy associated with said transmitting circuit.

ll. in a telephone systeni., a receiving circuit includingl a receiver and one of the windings of a transformer, a transmitting circuit associated with said receiving circuit and including the other winding of said transformer, said windings being conductivcly connected at both terminals, a transmitter and sourcel of energy associated with said transmitting circuit, and a line circuit associated with said receiving and transmitting` circuits.

l2. ln a telephone system, a receiving cir cuit including' a receiver and one of the windings of a ti'ansi'former, a transmittingl circuitassociated with said receiving circuit and including` the other winding of said transformer, said windings being' conductively connected at both terminals, a trans mitter and source of energy associated with said transmitting circuit, closed circuit conduct-ivcly connected with said transmitting' and receiving circuits and a line circuit associated with said closed circuit.

13. Yin a telephone system, a receiving circuit including a receiver and one of the windings of a transformer, a transmitting' circuit associated with said receiving circuit and including' the other winding of said transformer, the said windings being conductively connected at both terminals, a transmitter and source of energy associated with said transmitting' circuit, a closed oircuit conductively connected with said transmitting and receiving' circuits and a line circuit inductively related to said closed circuit.

14. In a telephone system, a receiving ci rcuit including a receiver and one of the windings of a transformer, a transmitting circuit associated with said receiving` circuit and including' the other winding' of said transformer, the said windings being' conductively connected at both terminals, a transmitter and source of energy associated with said transmitting' circuit, a line circuit and means associating said transmitting' and receiving' circuits serially with said line circuit at a point between the terminal stations.

15. 1n a telephone system, a receiving' circuit including' a receiver and one of the windings of a transformer, a transmitting circuit associated with said receiving circuit and including' the other winding' of said transformer, said windings being' conductively connected at both terminals, a transmitter and source of energy associated with said transmitting' circuit, a line circuit and a transformer having' three coils, one coil being conductively connected to said transmitting' and receiving' circuits and the other two being' connected in series with the two sides of the line circuit, respectively.

16. A telephone-repeater comprising' a receiving circuit including a repeater-'receiver and one of the windings of a transformer, a transmitting' circuit associated with said receiving circuit and including' the other winding of said transformer, said windings being' conductively connected, a repeater# transmitter and a source of energ'y associ;

subscribed my name this 15th day of April 1909.

HENRY B. STONE.

litnesses1 OLIVER KENDALL, Jr., JAMES H. GAULT.

ated with said transmitting' circuit, the said 

